The present invention relates to an endoprosthesis of the type filled with viscoelastic material and provided with cover plates at its end faces German Pat. No. 2,203,242 discloses such a prosthesis.
Its drawback is that the elastic material applied between the cover plates is not completely compatible with the human body since harmful long-term reactions with the surrounding body tissue cannot be permanently excluded.
Moreover, DE-OS 3,529,761, which corresponds to U.S. Pat. No. 4,759,766, discloses an intervertebral disk prosthesis in which a rigid spacer is provided between two symmetrical end plates. The end plates are movable relative to one another by the interaction of meshing pairs of convex and concave faces.
Here again there exists the drawback that the surfaces rubbing against one another create abrasion particles.